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Caption

Montage at 80,000 x. Artwork of influenza viruses attack respiratory epithelium cells causing aveolar breakdown and secondary infections of bacteria (pneumonia). The virions are pleomorphic, appearing spherical or tubular. The glycoproteins on the envelope are classified H-number, and N-number with an unlimited number of variations due to mutations called drift, or shift. After entering the cell through endocytosis, the viral envelope uncoats exposing the nucleocapsid which enters the nucleus where its RNA is transcribed into messenger RNA.